High bits of movmskp{s|d} and pmovmskb are known zero. rdar://10247336
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141371 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index fc2d5ce..a351fa5 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -12333,6 +12333,33 @@
KnownZero |= APInt::getHighBitsSet(Mask.getBitWidth(),
Mask.getBitWidth() - 1);
break;
+ case ISD::INTRINSIC_WO_CHAIN: {
+ unsigned IntId = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
+ unsigned NumLoBits = 0;
+ switch (IntId) {
+ default: break;
+ case Intrinsic::x86_sse_movmsk_ps:
+ case Intrinsic::x86_avx_movmsk_ps_256:
+ case Intrinsic::x86_sse2_movmsk_pd:
+ case Intrinsic::x86_avx_movmsk_pd_256:
+ case Intrinsic::x86_mmx_pmovmskb:
+ case Intrinsic::x86_sse2_pmovmskb_128: {
+ // High bits of movmskp{s|d}, pmovmskb are known zero.
+ switch (IntId) {
+ case Intrinsic::x86_sse_movmsk_ps: NumLoBits = 4; break;
+ case Intrinsic::x86_avx_movmsk_ps_256: NumLoBits = 8; break;
+ case Intrinsic::x86_sse2_movmsk_pd: NumLoBits = 2; break;
+ case Intrinsic::x86_avx_movmsk_pd_256: NumLoBits = 4; break;
+ case Intrinsic::x86_mmx_pmovmskb: NumLoBits = 8; break;
+ case Intrinsic::x86_sse2_pmovmskb_128: NumLoBits = 16; break;
+ }
+ KnownZero = APInt::getHighBitsSet(Mask.getBitWidth(),
+ Mask.getBitWidth() - NumLoBits);
+ break;
+ }
+ }
+ break;
+ }
}
}